Sliding caster



Mud! 1929- s. D. WENETSKY 1,704,416

SLIDING CASTER F11edJan.2l. 1927 PATENT OFFICE.

SOLOMON D. WENETsKY, OF DORCHESTER, MASSACHUSETTS.

smnma oas'rnn,

Application filed January 21, 1927. Serial No. 162,662.

This invention relates to that class of sliding casters or glides for the legs of furniture which comprise a sheet metal dome shaped device, from the rim or circular edge of which three or more inte ally formed prongs project, said rongs eing adapted to be driven into the eg, to hold the device in position and to provide a smooth surface for the end of the leg to which it is attached.

One of the chief difiiculties which have been encountered in the use of these devices is in the secure attachment thereof to the furniture leg, on account of the danger of splitting the wood, when the attaching prongs are driven therein. The tendency of the prongs to split the wood depends on several factors, one of the most im ortant of which, aside from size, is the istance from the point where the prong enters the wood to the adjacent side of the leg.

It is desirable to have the external diameter of the dome portion of the caster, at the point where it engages the wood, as great as possible in comparison to the width or diameter of the leg to which it is to be attached, but, where the outer sides of the prongs are flush with the outer edge of the rim of the dome, it is necessary, to avoid splitting, to

. employ a caster having a diameter which is substantiall less than the diameter or thickness of the eg.

To enable the use of a caster which approximates more nearly in diameter to the diameter or thickness of the leg, shding casters of this type have been produced in which the prongs were set in from the rim, this having been accomplished by indenting the dome part at the points where the prongs are connected thereto so as to set the prongs inward, also by slitting the rim of the dome in line with the side edges of the prongs and then bending the latter inward at the point of connection and folding the adjacent portions of the rim against the outer sides of the prongs. These constructions are, however, objectionable partly from the stand point of appearance, as the exterior of the dome is cut or indented, but largely for the reason that the indentations or sharp projections which are formed to set in the prongs, are liable to catch in the tufting of carpets or rugs, on which the casters are likely to be slid.

The objects of my invention are to provide a form of sliding caster 0f the type above referred to in which the prongs shall be set in from the edge of the dome portionto a substantially greater extent than what has previously been considered practicable, and at the same time, to produce a dome portion which is erfectly circular and is without slit or in entation therein and which is of substantially greater strength than similar devices of this character, so that it will have greatly increased rigidity at its rim and is unlikely to be distorted either by the act of driving the prongs into the wood or to be flattened or indented by subsequent use.

Also to provide a device having the above described characteristics which may be formed from sheet steel by a stamping or dieing operation.

I accomplish these objects in the manner hereinafter described and as illustrated in the accompanying drawings, in which Fig. 1 is a bottom plan view, Fig. 2 a

side elevation and Fig. 4 a top Ian view of a preferred embodiment of the lnvention.

Fig. 3 is a central sectional view at line 33 of Fig. 1.

Figs. 5 and 6 are plan and edge views of the original blank and Figs. 7 and 8 are sectional views indicating ste s in the forming operation.

As s own in the drawing the caster comprises a sheet metal piece shaped in dished form to provide a dome portion a having a base or rim portion b, on which a flat face 0 is formed and arranged to bear against the surface of the wood to which the device is attached, said rim portion being thickened or up-setat its edge to at least double the normal thickness of the material of which the caster is formed, and tapering in thickness to the middle portion of thedome, which is of normal thickness.

A series of prongs (Z, preferably three in number are formed integrally with the rim and project perpendicularly from said face in circular relation, with the inner sides thereof flush with the internal recess 0 formed in the inner side of the dome, the thickness of said prongs being the same as the normal thickness of the material, so that the outer sides of the prongs are at a distance from the outer periphery of the rim, or of face a, fully equal the thickness of the metal, whereby they are set in from outer surface of the dome to this extent.

In the formation of the caster, a blank of the shape indicated inFigs. 5 and 6, is cut from somewhat malleable sheet metal,

and, by the same, or a subsequent operation, the blank is drawn into the elongated dome form shown in Fig. 7, in which the sides of the dome portion are cylindrical, while the prongs are similarly shaped and form continuations of the cylindrical side portions. The shape and relative arrangement of the prongs is not changed by subsequent forming operations. By means of a swaging or tip-setting operation the elongated dome portion is then reshaped, so that the rim portion is spread out, this operation being performed by means of three dies, one of which tits against the inner sides of the prongs and forms at its end to final shape of the cavity in the inner side of the dome, the second of which bears against the outer sides of the prongs and conforms to the face 0 of the dome rim and the third of which conforms to the top surface of the dome, as indicated in Fig. 8.

With the above described construction, while the weight of metal required for its formation is slightly greater than that which would be required for a caster of equal diameter of the common type in which the prongs are flush with the outer edge of the rim, yet the increased amount of metal is advantageously employed to increase, very substantially, the strength of the rim, so that the dome part cannot be distorted or the prongs readily bent out of position by the driving in operation when attached.

Other important advantages are that a caster of substantially increased diameter may be employed for a furniture leg of a certain size without danger of causing split ting, as compared with glides of the common type, and, at the same time, a caster is produced in which all the exterior s rface thereof, which is exposed when attached, is entirely free from projections and indentations. Also, for a caster of a certain diameter, as compared with the type ha ing prongs flush with the rim or outer periphery, the attaching prongs may be made longer and stronger without increasing the danger of splitting the wood when the caster is attached, and, at the same time, the danger of bending the prongs, when they are driven into the wood, is reduced.

\Vhile the device could be made by a casting operation, it is highly advantageous to be able to make it by a dieing operation, as this enables it to be manufactured by automatic machinery and makes possible quanitity production at a low cost.

Iclaim:

1. A sliding caster for wooden furniture legs comprising a hollow dome having its edge-portion upset to form a thickened rim portion provided with a base face of greater width than the thickness of the material at the middle portion of the dome, and a series of attaching prongs integrally formed with the dome and projecting from said face at a substantial distance within the outer periphery thereof.

2. A sliding caster for wooden furniture legs comprising a sheet metal dome having its edge portion up-set to form a relatively thickened edge portion having a circular face arranged for engagement at its outer periphery with the surface of the wood to which it is attached, and a series of circularly arranged prongs formed integrally with the dome and projecting from said face at a substantial distance within said outer periphery.

3. A sliding caster for wooden furniture legs comprising a sheet metal piece shaped in dished form to provide a middle bearing portion of approximately the normal thick ness of the material and having a smooth exterior and a continuous rim portion up-set to form a base face of a width approximately double the thickness of said bearing portion and tapering in thickness to said bearing portion, and a series of circularly arranged prongs of the normal thickness of the material and extending continuously therewith from said face with their inner sides cylindrically arranged and continuous with the inner periphery of said face and with their outer sides at a substantial distance within the outer periphery of aid face.

A sliding caster for wooden furniture legs comprising a sheet metal dome having its edge portions up-set to form a thickened rim portion having a base face at its edge for engagement with the material to wl'iich it is attached, said edge portion tapering in thickness from said face to the normal thickness of the material at the middle portion of the dome and a series of attaching prongs formed integrally with the dome and projecting perpendicularly from said face at a substantial distance within the outer periphery thereof.

In testimony whereof, I have signed my name to this specification.

SQLOMON D. WENETSKY. 

